Page 251 - My FlipBook

than we watch the teeth of adult or of young persons, for
changes occur rapidly, the predisposition to decay is often
very severe, so that the teeth decay very quickly indeed,
and unless we keep a very close watch of them we will
find that they have decayed badly in the interim. Unfor-
tunately, our cememts are very unreliable. A cement that
we may use this week and find afterward that it is doing
good service mia}' not be goo'd next month. These changes
that occur in the cements are very vexatious. No means
has yet been devised by which they can be prevented.
Neither do we know very certainly, as yet, what constitutes
the changes that occur iii the cements. It is probable that
a portion oif the change occurs from the absorption of
water by the fluid portion ; certainly there is considerable
change occurring in that way, but there is some chemical
change occurring in the fluid that chemists do not seem
yet to be able to overcome completely. These changes
that occur after the cement has been put upon the market
is one thing that is troubling manufacturers very much in-
deed. The work upon the cements, however, is now more
vigorously prosecuted and along better lines than ever be-
fore, and there is strong hope that we will have better
cements in the near future. There is an effort being made
to make a phosphate of copper cement that promises a
good deal; yet, there is an objection to this cement in
the fact that it is very black. For that reason it is not
as suitable for fiHing front teeth, but it is very much harder
than the zinc cements, and for that reason it will stand
much better in positions where abrasion w'ill come upon it,
and the color is not particularly objectionable for the fill-
ing of molar teeth where it will not be in view. I have
tried this cement myself somewhat in the latter part of my
practice. It is being improved very materially within a year
or two, apparently, so that we hope it will be available for
more permanent work in children's teeth in the near future.
Of course, wherever we can, a gold filling is the right thing
to make, but the cases where we can make gold fillings
succesisfully in the teeth of little children are very few.
In the labial decays in ineisors and cuspids we may use
any of these means. It is true we cannot file them away
as we would file away the proximate decays, but we can open

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